Monday, September 26, 2011

After NASA finished it's space shuttle program, it has fallen to private industries to pick up the torch. Space flight should continue, but no longer in the hands of the government. The dream of private spaceflight is not just a vague hope, these companies already exist. The most notable of which is the company SpaceX (Space Exploration Technologies Corp.) founded by PayPal co-founder Elon Musk.

SpaceX logo

SpaceX is working in a private-public partnership with NASA to develop the next generation of rockets and space technologies that can be used for both commercial and government purposes. Under this partnership, SpaceX has developed the Falcon 1 and Falcon 9 rockets along with the Dragon capsule. As a launch mechanism, the Falcon 9 rocket is 6 times more cost effective than the rockets used to launch NASA's space shuttle. In the hopes that these cost effective mechanisms will continue to be created, both NASA and the United States Air Force have awarded SpaceX indefinite delivery/indefinite quantity (ID/IQ) contracts. This means that the Air Force can buy $100 million worth of launches, while NASA can purchase up to $1 billion.

Prototype of the Falcon 1 rocket

Falcon 9 rocket

SpaceX is working to be able to send cargo and the Dragon capsule to the ISS (International Space Station) this year. It will mark the beginning of this companies ability to transport cargo back and forth from the Earth into outer space. Along with it's various governmental contracts, SpaceX has also landed a contract with SES to put SES-8, a communications satellite, into orbit. All of these only make up a small percent of the contracts and prizes awarded to this company, sometimes it pays to be one of the first.

SpaceX Dragon capsule

Ultimately, the US government believes that private companies will be much more effective at developing space technologies than any government organization. Private companies have the incentive of profit. Governments don't send things into space to make money, so they aren't nearly as motivated to do well or develop cost effective systems. Another major argument for private space industry is that companies don't have all of the bureaucratic red tape that governments must have. Companies are capable of making quick decisions and working autonomously. We're all just going to have to hope that these companies really can deliver.

Friday, September 23, 2011

Today it was officially announced that European scientists have observed neutrinos traveling faster than the speed of light. Theoretically, nothing can go faster than the speed of light, so this claim is amazing. If this all pans out to be a real phenomenon, most of our physics knowledge will have to be re-evaluated. It's not often when you come upon an "everything you know could be wrong" situation.

Image of neutrino paths

This discovery was made by OPERA (Oscillating Project with Emulsion-tRacking Apparatus) and CERN (European Center for Nuclear Research). The CERN particle collider fired a beam of protons at a solid target, creating neutrinos which sped through 730 kilometers of earth to the OPERA neutrino detector.

The neutrinos travel through the earth

The neutrinos traveled this distance in 2.43 milliseconds, 60 nanoseconds faster than they should have. This is a small difference, but the experiment is supposed to have a margin of error of 10 nanoseconds, so this measurement should be valid.

OPERA neutrino detector

If this observation is accurate, it would unravel Einstein's theory of relativity. Over the years many theories have been based on Einstein's theory, so if it were to fall apart, most of what we know about physics would be wrong. I have heard some pretty extraordinary claims about what this all could mean. One of the more fantastic ones is that we might be able to violate causality by sending messages back in time. Another is that there is a warped 5th dimension in our universe where the speed of light is faster, and the particles just went through a pocket of this dimension. I don't believe any of this, it sounds more like bad science reporting than anything else. The final claim that I've heard, which makes infinitely more sense, is that the speed of a neutron will just become the maximum speed limit, not light.

Picture from the inside of the CERN particle collider

Nobody is assuming that this observation of the speed of neutrinos is correct. This is an extraordinary claim, so extraordinary that the researches who found it are assuming that there was some error in their measurements. They were incredibly rigorous in eliminating any errors that they could find however, so they published a paper to be scrutinized by the scientific community so that someone can figure out if anything went wrong. This experiment is to be verified in two other labs in the near future, no one is going to believe this claim until there is a lot of evidence to back it up. In science, we must remember that we don't really know anything, years of study and research can be overturned in a single night.

Tuesday, September 20, 2011

Now that the NASA space shuttle program is done, the US federal government has started investing money into private space companies. The idea is that these companies will continue to develop technologies to send people to space, and thus continue to advance our society.

NASA's glorious shuttle program has come to an end.

The shuttle program was supposed to be an amazing success of American engineering, with as many as 50 launches per year, but in reality it fell far short of its goals. The same technology that was used for the space shuttles back in the sixties was used right up until the programs end. There was very little development under the control of the government.

Technology in the space shuttles has changed very little

The benefits of putting space travel in the hands of private corporations are numerous. One of the biggest benefits is the lack of red tape. Because NASA's shuttle program was under the control of the federal government, it took a long time to get funding and to make any changes because of all the bureaucracy that had to be waded through. Ideally, private companies would be able to make snap decisions and implement new techniques whenever it looked beneficial. Competition between companies would spur inovation on a level not possible for any government run organization. There would be strong motivations to progress, because these corporations would be in it for the money, whereas governments don't have such prerogatives.

SpaceX is a private space travel company

The idea for these many space industries is that they would ferry people to space for money. There are rocket/jet hybrids that are capable of taking people just above the Earth's atmosphere, these are largely what space industries are looking at in the near future. Eventually it is likely that these businesses will be able to take people to the moon and back, for a price. Once technology is advanced enough, it will become feasible for these companies to run successful businesses off of space travel.

Thursday, September 15, 2011

You've probably heard that nicotine is the addictive chemical in cigarettes, but that's not all it is. Nicotine for common consumption usually comes from ingesting the tobacco plant, either through the lungs, the skin of the mouth or through the nose. Tobacco, however, is a member of the nightshade family, all of which contain the chemical nicotine. This means that the same chemical in that cigarette is also in the deadly nightshade.

Tobacco plant

Nightshade flower

In the tobacco plant, nicotine is synthesized in the roots of the plant and then stored in its leaves. The purpose of this chemical is as a repellent. Nicotine serves to discourage herbivores from eating the tobacco plant, especially insects. For a while, nicotine was even used as an insect repellent because of this property.

Nicotine is an insect repellent

Tobacco is an alkaloid chemical, similar to caffeine. Because of its properties as an alkaloid, nicotine can serve as a stimulant to mammals in small quantities. Higher doses can sedate or kill an animal. Nicotine burns at a lower temperature than it's boiling point, this is how the nicotine in a cigarette becomes a vapor that you inhale. This vapor has a fairly low combustion temperature however, around 308K (35 C), so most of the vaporized nicotine is burned up before it gets inhaled.

Most of the nicotine is being burned away.

This post is more about nicotine itself, but I would be remiss if I did not cover the health concerns associated with smoking and various tobacco related habits. Nicotine is a highly addictive substance. It can diffuse into your blood stream through your lungs, skin and mucus membranes. Once the chemical has entered your body, it can reach your brain in about 10 to 20 seconds. When nicotine reaches your brain, it triggers the release of dopamine, as well as other chemicals like adrenaline. Dopamine is what causes addictions. Dopamine is a form of positive feedback for the brain, it makes you feel good, and tells your body that what you just did was something good. This is essentially the same process that makes us eat, so it can become highly addictive.

Nicotine triggers the release of dopamine

As I mentioned, nicotine also triggers the release of adrenaline, which can invigorate the smoker. This adrenaline also triggers the release of glucose into the blood stream which provides energy, and can reduce the apetite of the smoker.

The harm from smoking doesn't just come from the smoke alone, nicotine also has a series of other negative effects on mammals, other than creating an addiction. Nicotine in the blood system can actually harden the arteries, causing severe heart disease. No matter how good it feels, smoking, taking snuff or chewing tobacco will all eventually kill you. Don't do it kids.

Tuesday, September 13, 2011

To finish up my articles about the planets, I'm going to talk about Mercury. This planet is the closest to the sun, and by far the smalles (now that Pluto has been knocked down to "planetoid"). Mercury is probably best known for being really hot, but in comparison to other planets in the solar system, it's refreshingly cool.

Mercury

Mercury rotates in such a way that one face is always pointed towards the sun. This, along with it's extreme proximity to the star, means that one side of the planet can get extremely hot, up to 700 K. By Earth standards, that would kill every living thing on the surface of the planet. This extreme temperature, however, is nothing compared to the internal temperature of planets like Jupiter. The face pointing away from the sun gets extremely cold. Even though the planet is so close to the star, there is no atmosphere to circulate the heat, and because this dark side never gets any sun, it can get down to as low as 90K.

Half of Mercury is forever bathed in shadow.

Mercury is a heavily cratered planet with no natural satellites. It's surface is very flat and closely resembles that of the moon. Mercury is one of only 4 terrestrial planets in our solar system, all the others are gaseous. The planet is 70% metallic and 30% silicate. It is smaller than the largest moons in the solar system, but it is more massive. Unlike our moon, this planet has an iron core which is enough to provide it with a magnetic field, though weak one. The magnetic field around Mercury is only 1% the strength of Earth's.

Surface of Mercury, taken by Messenger probe.

So far, little is known about the planet. We can only observe a small amount of it using terrestrial telescopes, and only one space probe has been able to map it so far. Another probe has been sent and will stay in orbit around Mercury to map it's surface, however, so we will one day know much more.

Sunday, September 11, 2011

I recently wrote an essay concerning the use of preparing for the zombie apocalypse, so I'll share it with you here.

Zombie Apocalypse

It may sound unlikely now, but the zombie plague is a very serious threat to humanity. Hollywood has long dramatized this threat to the point that no one can take it seriously anymore. Whenever the term “zombie apocalypse” is uttered, people invariably think of various movies, like Day of the Dead, or videogames like Dead Rising.Regardless of it’s largely cinematic prevalence in the public mindset, zombies are still a serious threat to our society that must be prepared for through personal disaster plans and general public awareness.

There already exists numerous diseases, like rabies [1], that are capable of driving infected creatures violent and insane. Who’s to say that something even more serious couldn’t infect the human population? Examples of “mind controlling” infections are present in abundance throughout nature, usually through parasites like the Cordyceps fungus [2]. The biggest argument against the possibility of a zombie apocalypse that I’ve heard is the claim that it’s impossible. This is a very shortsighted and ultimately dangerous belief. Those who claim that zombies are impossible are assuming that “zombies” refers to the walking dead. This is of course impossible, but that is certainly not the only way that a zombie could be created. A zombie could be a person or animal infected with a disease that takes control of the victims brain, making them seek out other creatures to infect or eat. Limiting the word “zombie” to only the living dead will invariably cause people to ignore this very serious threat. It is not much of stretch to imagine that something like this could enter the human population and cause an outbreak of epic proportions.

Preparing for a zombie outbreak really wouldn’t be that hard. Ultimately, a few preparations per person could save thousands, if not millions, of lives. When hordes of crazy infected people are coming to rip you to pieces, it’s always good to be able to defend yourself [3]. If this infection is truly be a “zombie plague” it will cause people to become violent and zombie like. For that to happen, the infection must alter the victim’s brain. In rabies we observe a marked decrease in the infected creatures motor skills [1] this means that the zombies are likely to have trouble walking and should be relatively slow. Because of this, merely living in a house with stairs could save your life. Owning weapons will also be very helpful. Having an axe or shotgun laying around the house could help to hold off the invading hordes until help arrives. All of these things are very cheap, and could save your life. Are a few dollars really worth the risk?

Even if the zombie apocalypse seems so unlikely that it shouldn’t be prepare for, preparing for the zombie apocalypse prepares you for other disasters as well. For almost all disasters, hurricanes being just one, you want to have a survival kit prepared [4]. You need first aid, food and water. All of these things are essential no matter is thrown your way, whether it be zombies or a giant storm. If zombies were to overrun your town, there would be no one to left to manage water facilities or to maintain the power supply. If the zombie infestation is this serious, your town will likely be quarantined, thus food will stop coming in, and you will be cut off from the rest of the world. It’s a good idea to have something to keep you going until you get rescued. As silly as it might sound, the CDC has even begun running zombie apocalypse scenarios and trying to increase public awareness about preparedness [5]. They claim that preparing for the zombie apocalypse is much the same as preparing for any other disaster.

Ultimately, it all comes down to willingness to take the risk of being unprepared. Even if there never is a zombie plague, you’re still prepared for any other disaster that might be looming over the horizon. There is very little to lose, but everything to gain, being prepared could mean the difference between life and death for yourself and your family, the choice is yours.

Wednesday, September 7, 2011

This is old news now, but antimatter has been found in abundance in outer space. A few months ago, positrons, anti-electrons, were found coming from atmospheric discharges (lightning) but this is different. This new antimatter discovery yielded antiprotons which are 2000 times more massive than positrons.

Diagram of radiation belts from NewScientist magazine.

This antimatter exists within the inner Van Allen radiation belt. The particles that are not instantly destroyed by touching regular matter get trapped by the Earth's magnetic field, holding them in a torus around the Earth. Here the particles have a much better chance of remaining for an extended period of time because there's not as much matter for them to interact with.

These antiprotons are thought to be created when cosmic rays interact with the Earth's atmosphere. Most often regular matter is created by these interactions, which serves to populate the Van Allen belts, but every now and then an antiproton will be created. Most of this antimatter is instantly destroyed upon impact with regular matter, but some of it manages to safely reach the inner Van Allen belt where it can exist for a while longer. Even with this low production rate, there is estimated to be more antimatter within the Van Allen belts than in any cosmic ray.

Example of cosmic rays

In 2006, PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) was launched to find this antimatter which had been theorized to exist. It orbited for 850 days and managed to pick up 28 antiprotons. This might sound like a very small amount, and it is, but it is much more antimatter than we can find anywhere else. One must also take into account that this probe only explored an incredibly small fraction of the Van Allen belts, so there's bound to be much more antimatter out there.

PAMELA space probe

The upshot of all this is that some reporters are saying that this antimatter may be enough to eventually fuel antimatter rockets. It's hard to tell if this is true or just an artifact of science reporting, but one thing is for sure, it's very exciting.

Sunday, September 4, 2011

The term "alpha particle" comes up a lot when discussing radiation, but I always found it to be rather nondescript. I decided to delve deeper, and it turns out to be pretty simple.

Alpha decay creates alpha particles

Alpha particles are pretty much helium ions.Two protons, two neutrons and a charge of +2 because there usually aren't any electrons. Not all helium nuclei that have these conditions are alpha particles though, that's where it gets confusing. Alpha particles are classified by how they were created. The two main methods for their creation are through alpha decay and ternary decay. There are other ways to create these helium nuclei, like in a particle accelerator for example, but those usually aren't called alpha particles.

The Large Hadron Collider is an example of a particle accelerator

Alpha decay happens when a heavy atom loses an alpha particle. Because an alpha particle contains two protons, that means that the decaying atom must lose those protons, thus it is actually turning into another particle altogether. Each element's properties are determined by the number of protons it contains, so an element undergoing alpha decay becomes a different element. Protons are held within the nucleus of an atom by the nuclear force, but the electromagnetic force is always pushing back, trying to separate the protons from each other. Most of the time the neutrons in the element provide enough spacing to keep the protons far enough apart, but sometimes this atom will still split apart. The alpha particle manages to escape through quantum tunneling, but I probably don't understand how that works myself, so I won't try to explain. When an alpha particle is produced through alpha decay, it usually has an energy of 5 MeV (mega electron volts). This is fairly weak. Your average alpha particle can usually be stopped by a few centimeters of air or by your skin. However, if you happen to ingest alpha particles or alpha producing radioisotopes, they will wreak havoc on your body. Alpha particles will give you radiation poisoning in relatively small amounts.

Relative penetration of various forms of radiation.

Another way in which alpha particles are formed is through ternary decay. This form of decay is somewhat similar to alpha decay, except three new particles are created instead of two. When alpha particles are emitted through ternary decay, they generally have an energy of around 16 MeV and nearly three times the penetrating power. Ultimately though, alpha particles are just another form of radiation. Just don't underestimate the little guys.

Thursday, September 1, 2011

Recently I have been getting involved with a lot of college level chemistry and physics experiments, and one of the most important things that I've had to focus on when writing lab reports has been the error in my experiments. To many students, this might seem like a tedious and ultimately futile task, but it is not so. Knowing where your errors are coming from, even knowing that you have errors, is very important in science.

It's best not to emulate them

When running experiments, humans make errors. There is almost no conceivable way for a human to do anything perfectly (appart from math and similar nonphysical tasks). No matter how hard one might try, there is always a margin of error. When measuring things with a ruler, that error is approximately plus or minus one half of the smallest unit that the ruler measures to.

It's not perfect

Sources of error can come from anywhere. The most important errors to realize are the errors in your measuring device. Sure your scale might measure to the nearest thousandth of a gram, but that really isn't all that accurate. If we assume that the scale rounds, then your scale has a built in error of plus or minus five ten-thousandths of a gram. Even if you did manage to have a scale that measured every single atom (I'm not sure how that'd be possible) there would still be error in your experiment. When you have measurements that fine, slight variations in air current alone can significantly alter your measured value.

Some scales are pretty accurate

So far I've said nothing about why knowing these errors is important, so let me remedy that now. Measurements are taken for a reason, whether it is to determine the molar mass of a molecule in a compound or to determine the average velocity of an air glider. You are looking for an answer, and you will want your measurement to be as accurate as possible. If you don't do enough experiments to minimize your randome error, you are very likely to get something wrong. Can you imagine what that would be like if some lab synthesized the wrong medicine because their experiments were done poorly? Or what if a part in your car had the wrong measurement? That medicine could kill you, and that part might fail or not even work in the first place. There are numerous other examples of why you need to know your error and account for it, but suffice it to say that it's important.